MECHANICS AND USEFUL ARTS. 29 



The iron stern-post is 13 inches in breadth, by 5 inches in thickness, carrying 

 the rudder, the stock of which is 8 inches in diameter. The framing of the 

 ship is very heavy. The space between each frame is only 10 inches, and 

 the powerful frames or ribs are themselves 10 inches deep, with double angle 

 irons at the outer and inner edges. The bow is constructed in a manner at 

 once peculiar and affording the greatest possible strength to this important 

 part of the ship. The framing is placed normally to the stern, the effect of 

 which is that, in the case of collision with other ships or with rocks, or ice- 

 bergs, the strain would fall upon the very strongest material within the 

 structure. The plates or outer planking of the ship, so to speak, are laid 

 alternately, so that one adds strength to the other, and they form a whole of 

 wonderful compactness and solidity. The keel plates are J-^- of an inch in 

 thickness; at the bottom of the ship the plates are i| of an inch in thickness; 

 from this section to the load water line they are f of an inch, and above 

 this they are i| of an inch in thickness. The plates round the gunwale 

 are |- of an inch in thickness. 



The Persia has seven water-tight compartments. The goods are to be 

 stowed in two of these divisions. These goods' stores, or rather tanks, are 

 placed in the center line of the ship, with the coal cellars or bunkers on each 

 side of them. At the same tune, the vessel is so constructed as to have hi 

 reality a double bottom under these goods' chambers so that if the outer 

 were beat in or injured, the inner would, in all likelihood, protect the cargo 

 dry and intact. The chambers are perfectly water-tight ; and in the event of 

 accident to the hull, these tanks would of themselves float the ship. 



Steamer Ocean Bird. About three years ago the project of establishing a 

 line of European steamers from New York, to make the passage across the 

 Atlantic to the nearest port -on the coast of Ireland, within one week, was 

 broached- by Mr. William Norris, an eminent engineer of Philadelphia, who, 

 together with several distinguished gentlemen of New York, commenced the 

 enterprise. Mr. John W. Griffiths (now editor of The Nautical Magazine), 

 marine architect of New York, was instructed to build a steamship capable 

 of going 20 nautical miles an hour, that would accommodate from 60 to 80 

 passengers, and coal enough for 3.000 miles of steaming, at a cost of not more 

 than $120,000. Mr. Griffiths submitted his plans for a steamer capable of 

 attaining this speed, with a mean draught of water of 7 feet, so modeled that 

 she would lift her bows over the wave instead of cleaving it, and be sustained 

 by the middle of her length rather than by the ends, thus removing the main 

 cause of pitching or divergence from the horizontal position, and enabling the 

 hull to glide over instead of cutting through the water. The plans were 

 approved, the work progressed satisfactorily toward completion, and the 

 vessel was nearly ready for launching, when the failure of Mr. Norris brought 

 her under the hammer of the United States Marshal. The present owner 

 not choosing to complete her according to this original plan, Mr. Griffiths 

 declined proceeding with her construction, and she was consequently finished 

 by other parties, with modifications. These consisted in a reduction of five 

 per cent, of the propelling power, the addition of another deck weighing 194 

 tons, making four decks altogether, and a curtailment of three feet in the 



